nfs_page.h 6.8 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217
  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. /*
  3. * linux/include/linux/nfs_page.h
  4. *
  5. * Copyright (C) 2000 Trond Myklebust
  6. *
  7. * NFS page cache wrapper.
  8. */
  9. #ifndef _LINUX_NFS_PAGE_H
  10. #define _LINUX_NFS_PAGE_H
  11. #include <linux/list.h>
  12. #include <linux/pagemap.h>
  13. #include <linux/wait.h>
  14. #include <linux/sunrpc/auth.h>
  15. #include <linux/nfs_xdr.h>
  16. #include <linux/kref.h>
  17. /*
  18. * Valid flags for a dirty buffer
  19. */
  20. enum {
  21. PG_BUSY = 0, /* nfs_{un}lock_request */
  22. PG_MAPPED, /* page private set for buffered io */
  23. PG_CLEAN, /* write succeeded */
  24. PG_COMMIT_TO_DS, /* used by pnfs layouts */
  25. PG_INODE_REF, /* extra ref held by inode when in writeback */
  26. PG_HEADLOCK, /* page group lock of wb_head */
  27. PG_TEARDOWN, /* page group sync for destroy */
  28. PG_UNLOCKPAGE, /* page group sync bit in read path */
  29. PG_UPTODATE, /* page group sync bit in read path */
  30. PG_WB_END, /* page group sync bit in write path */
  31. PG_REMOVE, /* page group sync bit in write path */
  32. PG_CONTENDED1, /* Is someone waiting for a lock? */
  33. PG_CONTENDED2, /* Is someone waiting for a lock? */
  34. };
  35. struct nfs_inode;
  36. struct nfs_page {
  37. struct list_head wb_list; /* Defines state of page: */
  38. struct page *wb_page; /* page to read in/write out */
  39. struct nfs_lock_context *wb_lock_context; /* lock context info */
  40. pgoff_t wb_index; /* Offset >> PAGE_SHIFT */
  41. unsigned int wb_offset, /* Offset & ~PAGE_MASK */
  42. wb_pgbase, /* Start of page data */
  43. wb_bytes; /* Length of request */
  44. struct kref wb_kref; /* reference count */
  45. unsigned long wb_flags;
  46. struct nfs_write_verifier wb_verf; /* Commit cookie */
  47. struct nfs_page *wb_this_page; /* list of reqs for this page */
  48. struct nfs_page *wb_head; /* head pointer for req list */
  49. unsigned short wb_nio; /* Number of I/O attempts */
  50. };
  51. struct nfs_pgio_mirror;
  52. struct nfs_pageio_descriptor;
  53. struct nfs_pageio_ops {
  54. void (*pg_init)(struct nfs_pageio_descriptor *, struct nfs_page *);
  55. size_t (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *,
  56. struct nfs_page *);
  57. int (*pg_doio)(struct nfs_pageio_descriptor *);
  58. unsigned int (*pg_get_mirror_count)(struct nfs_pageio_descriptor *,
  59. struct nfs_page *);
  60. void (*pg_cleanup)(struct nfs_pageio_descriptor *);
  61. struct nfs_pgio_mirror *
  62. (*pg_get_mirror)(struct nfs_pageio_descriptor *, u32);
  63. u32 (*pg_set_mirror)(struct nfs_pageio_descriptor *, u32);
  64. };
  65. struct nfs_rw_ops {
  66. struct nfs_pgio_header *(*rw_alloc_header)(void);
  67. void (*rw_free_header)(struct nfs_pgio_header *);
  68. int (*rw_done)(struct rpc_task *, struct nfs_pgio_header *,
  69. struct inode *);
  70. void (*rw_result)(struct rpc_task *, struct nfs_pgio_header *);
  71. void (*rw_initiate)(struct nfs_pgio_header *, struct rpc_message *,
  72. const struct nfs_rpc_ops *,
  73. struct rpc_task_setup *, int);
  74. };
  75. struct nfs_pgio_mirror {
  76. struct list_head pg_list;
  77. unsigned long pg_bytes_written;
  78. size_t pg_count;
  79. size_t pg_bsize;
  80. unsigned int pg_base;
  81. unsigned char pg_recoalesce : 1;
  82. };
  83. struct nfs_pageio_descriptor {
  84. struct inode *pg_inode;
  85. const struct nfs_pageio_ops *pg_ops;
  86. const struct nfs_rw_ops *pg_rw_ops;
  87. int pg_ioflags;
  88. int pg_error;
  89. const struct rpc_call_ops *pg_rpc_callops;
  90. const struct nfs_pgio_completion_ops *pg_completion_ops;
  91. struct pnfs_layout_segment *pg_lseg;
  92. struct nfs_io_completion *pg_io_completion;
  93. struct nfs_direct_req *pg_dreq;
  94. unsigned int pg_bsize; /* default bsize for mirrors */
  95. u32 pg_mirror_count;
  96. struct nfs_pgio_mirror *pg_mirrors;
  97. struct nfs_pgio_mirror pg_mirrors_static[1];
  98. struct nfs_pgio_mirror *pg_mirrors_dynamic;
  99. u32 pg_mirror_idx; /* current mirror */
  100. unsigned short pg_maxretrans;
  101. unsigned char pg_moreio : 1;
  102. };
  103. /* arbitrarily selected limit to number of mirrors */
  104. #define NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX 16
  105. #define NFS_WBACK_BUSY(req) (test_bit(PG_BUSY,&(req)->wb_flags))
  106. extern struct nfs_page *nfs_create_request(struct nfs_open_context *ctx,
  107. struct page *page,
  108. unsigned int offset,
  109. unsigned int count);
  110. extern void nfs_release_request(struct nfs_page *);
  111. extern void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
  112. struct inode *inode,
  113. const struct nfs_pageio_ops *pg_ops,
  114. const struct nfs_pgio_completion_ops *compl_ops,
  115. const struct nfs_rw_ops *rw_ops,
  116. size_t bsize,
  117. int how);
  118. extern int nfs_pageio_add_request(struct nfs_pageio_descriptor *,
  119. struct nfs_page *);
  120. extern int nfs_pageio_resend(struct nfs_pageio_descriptor *,
  121. struct nfs_pgio_header *);
  122. extern void nfs_pageio_complete(struct nfs_pageio_descriptor *desc);
  123. extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t);
  124. extern size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc,
  125. struct nfs_page *prev,
  126. struct nfs_page *req);
  127. extern int nfs_wait_on_request(struct nfs_page *);
  128. extern void nfs_unlock_request(struct nfs_page *req);
  129. extern void nfs_unlock_and_release_request(struct nfs_page *);
  130. extern struct nfs_page *nfs_page_group_lock_head(struct nfs_page *req);
  131. extern int nfs_page_group_lock_subrequests(struct nfs_page *head);
  132. extern void nfs_join_page_group(struct nfs_page *head, struct inode *inode);
  133. extern int nfs_page_group_lock(struct nfs_page *);
  134. extern void nfs_page_group_unlock(struct nfs_page *);
  135. extern bool nfs_page_group_sync_on_bit(struct nfs_page *, unsigned int);
  136. extern int nfs_page_set_headlock(struct nfs_page *req);
  137. extern void nfs_page_clear_headlock(struct nfs_page *req);
  138. extern bool nfs_async_iocounter_wait(struct rpc_task *, struct nfs_lock_context *);
  139. /*
  140. * Lock the page of an asynchronous request
  141. */
  142. static inline int
  143. nfs_lock_request(struct nfs_page *req)
  144. {
  145. return !test_and_set_bit(PG_BUSY, &req->wb_flags);
  146. }
  147. /**
  148. * nfs_list_add_request - Insert a request into a list
  149. * @req: request
  150. * @head: head of list into which to insert the request.
  151. */
  152. static inline void
  153. nfs_list_add_request(struct nfs_page *req, struct list_head *head)
  154. {
  155. list_add_tail(&req->wb_list, head);
  156. }
  157. /**
  158. * nfs_list_move_request - Move a request to a new list
  159. * @req: request
  160. * @head: head of list into which to insert the request.
  161. */
  162. static inline void
  163. nfs_list_move_request(struct nfs_page *req, struct list_head *head)
  164. {
  165. list_move_tail(&req->wb_list, head);
  166. }
  167. /**
  168. * nfs_list_remove_request - Remove a request from its wb_list
  169. * @req: request
  170. */
  171. static inline void
  172. nfs_list_remove_request(struct nfs_page *req)
  173. {
  174. if (list_empty(&req->wb_list))
  175. return;
  176. list_del_init(&req->wb_list);
  177. }
  178. static inline struct nfs_page *
  179. nfs_list_entry(struct list_head *head)
  180. {
  181. return list_entry(head, struct nfs_page, wb_list);
  182. }
  183. static inline
  184. loff_t req_offset(struct nfs_page *req)
  185. {
  186. return (((loff_t)req->wb_index) << PAGE_SHIFT) + req->wb_offset;
  187. }
  188. static inline struct nfs_open_context *
  189. nfs_req_openctx(struct nfs_page *req)
  190. {
  191. return req->wb_lock_context->open_context;
  192. }
  193. #endif /* _LINUX_NFS_PAGE_H */